According to documents provided by former NSA contractor Edward Snowden, the effort to build “a cryptologically useful quantum computer” — a machine exponentially faster than classical computers — is part of a $79.7 million research program titled “Penetrating Hard Targets.” Much of the work is hosted under classified contracts at a laboratory in College Park, Md.

The development of a quantum computer has long been a goal of many in the scientific community, with revolutionary implications for fields such as medicine as well as for the NSA’s code-breaking mission. With such technology, all current forms of public key encryption would be broken, including those used on many secure Web sites as well as the type used to protect state secrets.

Physicists and computer scientists have long speculated about whether the NSA’s efforts are more advanced than those of the best civilian labs. Although the full extent of the agency’s research remains unknown, the documents provided by Snowden suggest that the NSA is no closer to success than others in the scientific community.